Combined take-up and safety lock



Aug. 29, 1933. E. v FRANCIS Er AL 1,925,022

COMBINED TAKE-UP AND SAFETY LOCK Original Filed Feb. 14, 1930 2 Sheets-Sheet 1 HIHH /NVENTORS Ear/e l/. Franc/'5 LO ano Aug- 29, 1933- E. v. FRANcxs Er AL V1,925,022

COMBINED TAKE-UP AND SAFETY LOCK Original Filed Feb'. 14, 1930 2 Sheets-Sheet 2 /NVEHTORS Ear/e V Franc/5 and /ex/' W Lemmon.

Patented Aug. 29, 1933 UNTED STATES erreur optics bus, Ohio,

assigne-rs to The Jeffrey Manufacturing Conipany, Columbus, Ohio, a corporation of h10 Griginal application No. September 18, 1931.

14 Claims.

This invention relates to a coinbined take-up and safety lock for shafts of endles conveyors.

An important object of the invention is to provide means for taking up slack in an endless conveyor element which has associated there'- with a back stop or safety lool; for preventing accidental reverse movement of the conveyor element and to provide an arrangement whereby adjustment of the conveyor to take up slack does not interfere withthe operation of the back stop and the oack stop does not interfere with the adjustment of the conveyor.

Another object of the invention is to provide the back stops with yielding ahutnients which l are connected for relieving the conveyor parts from excessive shocks when stopped with a load imposed thereon.

A further object of the invention is to provide means for automatically closing the openings in the conveyor housing about both ends of the shaft when the latter is adjusted so that the housing will effectively exclude deleterious matter and will coni-lne the material being handled.

A still further object of the invention is to provide simple and eiiicient means for adjustably mounting both ends of a conveyor shaft and a common operating means for eecting their simultaneous adjustment.

Other objects and advantages of the invention will become apparent during the course of the following description.

rIhe present application is a division of our copending application, Serial No. 428,379, iiled February le, i930, an improvement in combined take-up and safety lock.

In the accompanying drawings forming a part of the description and wherein like numerals are employed to designate like parts throughout the several views,

Figure 1 is a side elevation of the head end of an elevator illustrating the invention applied thereto.

Figure 2 is a vertical section of the same, taken on the line 2-2 of Figure 1.

Figure 3 is an elevation of the back of a portion of elevator housing looking from the left of Fig. l.

Figure 4 is an enlarged horizontal on the line 4-4 of Figure 1, and

Figure 5 is an enlarged detail sectional view of the closure plate guide on line 5%5 of Figure l.

As one example of the invention, it has here been illustrated in conjunction with an endless bucket elevator, but it is to be understood that the invention is not confined to this particular section taken 5o February 14, 1930, Serial 428,379. Divided and this application Seriai No. 563,654 (Cl. 1548-208) use and it may be effectively used in other fields. A vertical elevator housing or support 5 is provided to enclose a bucket elevator including a head shaft 6, especially when light and uiy material is being handled and is equipped with a discharge spout 7, communicating with the housing at the point where the buckets of the elevator discharge centrifugally, to receive and convey the discharged material to a point of storage or further handling. The head shaft 6 within the housing has keyed thereto a pair of spaced sprocket wheels 8 over which are trained the spaced endless chains 9 of the endless conveyor elements, which have connected thereto in any weil known manner, elevator buckets 10. The endless chains 9 are, of course, trained about similar sprockets secured to a foot shaft, not shown, disposed at the lower end of the elevator housing 5 andinotive powerv to the conveyor is transmitted through the shaft 6, which may have associated with one end 11 thereof any desired form of power transmission element, not shown; or the head shaft may, if desired, be a prime mover shaft such as the armature shaft of an electric motor mounted in any suitable manner.

From Figure 2 it will be seen that opposite ends of the head shaft 6 project out through openings l2 in opposite sides cf the elevator housing and are journaled in sectional bearings 13 fastened to the lower horizontal bar 14 of a vertically movable bearing frame indicated in its entirety by the numeral 15. Each bearing frame is composed of a pair of vertical horizontally spaced grooved side bars 16, each of which consists of a pair of oppositely facing spaced angie bars 17 with a ller strip 1,8 disposed therebetween to retain the adjacent faces of the angle bars in spaced relation to provide a groove 19 in the longitudinal outer edge of the side bar to embrace guides of 4a guide frame 2O secured in fixed relation to the elevator housing as will be more fully described hereinafter. The lower horizontal bar 14 of each bearing frame is composed of a pair of oppositely facing angle hars 2l which have their horizontal flanges 22 arranged in the same plane vto form a support to which the bearings 13 are bolted by the bolts 23. These angle bars 21 are secured at their ends to the vertical angle bars 17 by means of angle cleats 24.

Each bearing frame has its transverse top rail composed of a pair of horizontally spaced channel bars 25 held in spaced relation to each other and secured to the vertical angle bars 17 by means of upper and lower angle cleats 26 and 27, respectively. Thus it will be seen that each bearing frame comprises generally a substantially rectangular frame.

These bearing frames are mounted for vertical adjustment in a substantially rectangular guide frame indicated in its entirety by the numeral 2O and has its two vertical legs and its lower horizontal portion formed T-shape in cross section as best appreciated from Figure so that the stems of the vertical legs will' be disposed in the grooves 19 of the 'nearing frame to slidably mount the same. This guide frame 20 is composed of a pair of sections bolted together along vertical lines 23 and rests upon horizontal beams 29 secured to the elevator housing. Each of these beams 29 consists of a pair of oppositely facing angle braces 30 juxtaposed with their horizontal flanges arranged in a horizontal plane for the stable support of the base of the guide frame to which they are bolted as best seen in Figure 2. The tops of the guide frames 2O are secured in 'fixed relation to opposite sides of the elevator housing by means of a pair of horizontal transverse channel beams 30 which rest upon the top of the elevator housing and are secured at oppoe site ends to the upper portions of the guide frames 20.

The top cross bar 3l of each guide frame 20 is sectional as hereinbefore stated and joined along the line 28 at which point a vertical bearing 32 with anti-friction means is provided for the support of a nut 33 having a depending sleeve exten sion 34 which extends through the bearing 32 for mounting, About the upper hub of each nut is fixedly attached a horizontally disposed worm wheel 35. A screw sh ft 36 extends tl'irough the nut 33 at its upper end and its lower end is equipped with an eyelet disposed between the `channel bars 25 of the vertically adjustable bearing frame to be pivotally connected thereto on a horizontal axis by means of a pin 37. Rotation of the nut 33 will effect vertical movement of the screw shaft 36 and consequently the bearing Vframe l5. Since one of these bearing frames and adjusting mechanisms is provided on each side of the elevator housing for the two ends of the head shaft 6, it is desirable to provide means for simultaneously adjusting the bearing frames to the same degree simultaneously and for this purpose common operating means in the form of a horizontally disposed shaft 38 is mounted in bearings 39 fixed to the tops of the guide frames 20 on opposite sides of the housing. This shaft 33 is equipped at each end with a worm 40 for mesh with the worm wheels 35 and a hand wheel 4l is fixed to the shaft 38 for rotating it in either direction to cause simultaneous rotation of the nuts 33 to effect simultaneous movement of the two bearing frames l5.

Due to the fact that thehead'shaft 6 is vertically adjustable in the elevator housing, necess arily the openings 12 in opposite sides thereof must be of sufficient size to permit of vertical movements of the head shaft. Now, in order to keep the openings l2 of the housing closed regardless of the position of the shaft 6 with respect thereto, to exclude deleterious material from the elevator housing and to confine material being handled therein when its nature is such as to possess tendencies to escape during agitation caused by loading and unloading from the bucket elevator, rectangular closure plates 42 are movable with the head shaft 6 and overlap the edges of the openings l2 in all positions of adjustment of the head shaft. One of such closure plates 42 is provided for each end of the shaft 6 where it extends through the casing 5 and in this instance is provided with a circular aperture to closely embrace an annular flange 44 of a back stop device to be presently described. As best seen in Figures 2 and 5, each plate 42 has its vertical edges slidably mounted in Vertical guideways 61 provided on the casing 5. The closure plates 42 are held in proper position by braces 42 secured thereto and to the horizontal top rails 25 of the bearing frame l5. As is evident in Figure 2, the upper and lower flanged edges of each plate 42 overlap the upper and lower edges of the openings l2 in all positions of adjustment of the closure plates. From the foregoing description it will be evident that the head shaft 6 can be vertically adjusted to take up slack in the bucket elevator chains 9 by reason of the bearings 13 on the shaft being movable with the bearing frames 15 along the guides constituted by the vertical legs of the guide frame 20.

As is well understood in this art, a bucket elevator will reverse its rotation when the motive power is cut off and the buckets are loaded due to the loaded condition of the buckets along one run of the elevator and the empty condition of those along the opposite run, unless a check of some kind is provided to prevent such reverse rotation tendencies. If no check is provided the reverse movement of the elevator will attain great impetus due to the loaded condition of the buckets on one side and will cause them to move backwardly of their intended movement to prematurely discharge their contents back at the loading point to say nothing of the damage inflicted upon the elevator incident to its accidental reverse movement. Accordingly, provision has been made for a check or back stop to prevent such reverse rotation of the elevator which is of a character to faithfully perform its functions as well as to permit of the vertical adjustment of the elevator shaft to take up slack in the elevator chains. A check or back stop is provided for each end of the head shaft 6 and as they are identical, a description of one will suilice for both. Each of these back stops includes a circular plate 43 secured to the outer face of each sprocket 8. This plate 43 is equipped with an annular flange 44, the outer margin of which is angularly disposed as at 45 to be arranged in spaced parallel relationship with the main body of the plate. Between the flange 45 and the plate 43 a plurality of gravity actuated pawls 46 are pivotally mounted for cooperation with a ratchet wheel 47 loosely mounted upon the head shaft 6 between the sprocket 8 and the bearing 13 as best seen in Figure 2. It will be noted from Figure 1 that a vernier relationship exists between the arrangement of the pawls 46 and the teeth of the ratchet wheel 47, so that in every position of the sprocket 8 and pawl carrying plate 43, at least one of the pawls 46 will be properly engaged with the ratchet wheel 47. The flange 44 is disposed in the opening of the closure plate 42 and to more effectively seal the joint between these elements an outwardly projecting ange k48 is carried by the flange 44 to overlap the closure plate 42 at its juncture with the flange.

The teeth of the ratchet wheel 47 obviously face in a direction to cooperate with any ofthe pawls to stop reverse rotation of the head shaft. In order to constitute an abutment .for this purpose the ratchet plate 47 is provided with an extended arm 49 which extends between .the guide frame 20 and the housing 5 and through a vertical slot 50 in a .brace 5l secured to the housing. The 1 outer end of each arm'49 is connected to the -lower end of a coiled tension spring 52, the upper end of which is connected by a vertically adjustable of an equalizing bar 54. This equalizing bar is suspended between its ends by an eyelet 55 adjustable with respect thereto and connected to an eye bolt 56, depending from an angle bar 57 secured to the elevator housing as shown. Thus, it will be seen that a yielding abutment is vprovided for each back stop and that they are connected to equalize the stresses imposed upon the parts when the back stops act to prevent reverse rotation of the elevator mechanism. Excessive movements of the arms 49 ccnstituting parts of the yieldable abutments are stopped, by their engagement with opposite ends of the slots 50. Due to this particular anchorage of the abutments for the back stops, it will be obvious that no interference is offered thereby against vertical adjustments of the head shaft carrying the back stop mechanism, and, moreover, the yielding abutments through the adjustment of the eye bolts 53 and 55 can be made to compensate for the adjustments of the head shaft, should such be required. During normal operations of the bucket elevator, the pawls 46 will be swung by centrifugal force clear of the teeth of the ratchet wheels 47 and into engagement with the overhanging flange 44l to ride thereon'and insure quiet operation, but whenever motive power to the bucket elevator is turned off with the buckets loaded, the elevator will tend to move in a reverse direction and one of the absorb the shocks incident to stopping reverse movement of the bucket elevator. Preferably, the teeth of the wheels 47 and the relative positions of the pawls 46 with respect thereto on opposite ends of the shaft is the same, so that both back stops are effective simultaneously to prevent reverse rotation of the elevator.

It is to be understood that various changes in the arrangement,

pended claims.

What I claim is:

l. The combination with an elevator mechanism including a frame, a sectional guide frame mounted thereon and having parallel guide rails, a bearing formed between meeting sections of the guide frame, a bearing frame slidably associated with said guide rails, a conveyor shaft mounted in the bearings of said bearing frame, a nut mounted tended through said nut.

2. The combination with an elevator mechanism including a frame, a sectional guide frame mounted thereon and having parallel guide rails, a bearing formed between meeting sections of the guide frame, a bearing frame slidably associated with said guide rails, upper and lower cross bars connecting said side rails, a bearing mounted upon said lower cross bar, a conveyor shaft mounted in said last named bearing, a nut mounted in the bearing of said guide frame, and a screw shaft connected to said bearing frame and extended through said nut.

G. In a conveyor mechanism comprising a shaft, an endless draft device guided about the shaft, means supporting said shaft for adjustment in the longitudinal direction of the draft device to affect the tension of the latter, means operable to adjust said ble, the combination of shutter plates freely embracing the shaft and covering the the Shaft-emhaving apertures through jects and in which it is combination of shutter plates freely embracing the shaft and covering the apertures, connecting means exclusive of the shaft between the shutter plates and supporting means whereby the plates are adjusted in conjunction with the supporting means, and radial flanges supported on the shaft and rotatable therewith in overlying relation to the shaft-embracing margins of the plates.

5. In a conveyor mechanism comprising a shaft, an endless draft device guided about the shaft. means supporting said shaft for adjustment in the longitudinal direction of the draft device to affect the tension of the latter, means which the shaft profreely adjustable, the

comprising a guided about the housing having apertures through which the` shaft projects and in which it is freely adjustable, the combination of back-stop devices including outwardly faced dished elements fixed on the shaft, means supporting said shaft for adjustment in the longitudinal direction of the draft device to affect the tension of the latter, means operable to adjust said supporting means and to hold the latter in adjusted position, and a fixed housing having apertures through which the shaft projects and in which it is freely adjustable, the combination of back-stop devices including outwardly faced dished elements faced on the shaft in said apertures and supporting pawls on their outer sides, shutter plates freely embracing the shaft and covering the apertures, saidl plates being adjustable With/the shaft, and radial flanges on said elements in overlying relation to the shaft-embracing margins of the plates.

8. In a conveyor mechanism comprising a shaft, an endless draft device guided about the shaft, means supporting said shaft for adjustment in the longitudinal direction of the draft device to affect the tension of the latter, means operable to adjust said supporting means and to hold the latter in adjusted position, and a fixed housing having apertures through which the shaft projects and in Vwhich it is freely adjustabile,V the combination of back-stop devices including outwardly faced dished elements fixed on the shaft in said apertures and supporting pawls on their outer faces, shutter plates freely embracing said dished elements and covering said apertures, connecting means exclusive of the shaft between the shutter plates and supporting means whereby the plates are adjusted in conjunction with the supporting means, and radial flanges on said elements in overlying relation to the shaft-embracing margins of the plates.

9. The combination With an elevator mechanism including a support, an elevator head shaft adjustable with respect thereto, means vfor adjusting said shaft, a plurality of back stop devices associated with said shaft, each back stop device including an abutment, an equalizing bar connected to said support, and yielding means connecting said abutments with said bar.

10. The combination with an elevator mechanism including a support, an elevator head shaft adjustable with respect thereto, means for adjusting said shaft, a plurality of back stop devices associated With said shaft, each back stop device including an abutment, an equalizing bar connected to said support, and adjustable means connecting said abutments `with said bar.

11. The combination with Y conveyor mechanism including a support, a shaft journaled for trans-axial adjustment relative to said support, means operable to effect such adjustment, a pawl rotatable with the shaft and adjustable therewith, a ratchet concentric with the shaft and cooperable with the pawl, the ratchet being adjustable with the shaft, and means connecting the ratchet and support and operative in all adjusted positions of the shaft to restrain the ratchet against rotation.

12. The combination with conveyor mechanism including a support, a shaft journaled for transaxial adjustment relative to said support, means operable to'eifect such adjustment, a pavvl rotatable with the shaft and adjustable therewith, a ratchet concentric with the shaft and cooperable with the pawl, the ratchet being adjustable With the shaft, and an arm interposed between the ratchet and support to restrain the ratchet against rotation in all adjusted positions of the shaft.

13. The combination with conveyor mechanism including a support, a shaft journaled for transaxial adjustment relative to the support, means for effecting such adjustment, and a backstop for the shaft comprising cooperating pavvl and ratchet elements arranged to participate in the adjustment movements of the shaft.

14. The combination with conveyor mechanism including a support, a shaft journaled for transaxial adjustment relative to the support, means for effecting such adjustment, a backstop for the shaft comprising cooperating paWl and ratchet elements arranged to participatein the adjustment movements of the shaft, one of said elements being mounted in connection with the shaft, and means yieldingly connecting the other with the support.

EARLE V. FRANCIS. ALEXIS W. LEMMON. 

